IUCN - Facts and figures on Climate Change

Facts and figures on Climate Change

26 April 2012 | Fact sheet

State of play

Globally, 14 of the past 15 years have been the warmest on record.
The current pace of global average temperature rise puts approximately 20-30% of plant and animal species at increased risk of extinction.
All but 100 of 1,100 glaciers researched are receding (more ice melts in summer than re-forms the next winter).
Floods and droughts will become more common. Rainfall in Ethiopia, where droughts are already common, could decline by 10% over the next 50 years.
The Intergovernmental Panel on Climate Change (IPCC) predicts that by 2020, 75-250 million people in Africa will be exposed to increased water stress due to climate change.

The power of nature

Natural ecosystems capture more than 4.7 gigatonnes of carbon (GtC) annually.
Protected areas store 15% of terrestrial carbon and safeguard ecosystem services such as protection from disasters such as floods and securing water and food supplies.
The role of wetlands in reducing flooding associated with hurricanes in the United States is valued at an average of US$ 8,240 per hectare per year, with coastal wetlands in the US estimated to provide US$ 23.2 billion a year in storm protection services.
Protected areas in Bolivia, Mexico and Venezuela contain around 25 million hectares of forest, storing over 4 billion tonnes of carbon, estimated to be worth between US$ 45 and US$ 77 billion in terms of avoided global damage.
Protection of 1.63 million hectares of virgin taiga forests and peat soils in the Komi Republic, Russian Federation, will ensure a reduction of greenhouse gas emissions equivalent to 1.75 million tonnes of CO2 between 2010 and 2020.
Occupying only 2% of seabed area, vegetated wetlands represent 50% of carbon transfer from oceans to sediments.

The economic costs

The German Institute for Economic Research estimates that if nothing is done to curb greenhouse gas emissions, annual economic damages could reach US$ 20 trillion by 2100.
The same study found that immediate adoption of climate protection policies could limit the temperature increase to 2°C and eliminate more than half of the damages; by 2100 this would avoid US$ 12 trillion in annual damages by spending $3 trillion per year on climate protection.
Extreme storms and flooding in the UK are likely to become more frequent and more severe. By 2080 the annual cost of flooding in the UK could be £22 billion, or 15 times what it is today.
Climate change is increasing the frequency and intensity of extreme weather, causing a sharp upswing in damages. In 2005, natural catastrophes caused US$ 220 billion worth of damage worldwide.

Wildlife impacts

Some species are much more susceptible to climate change impacts than others due to biological traits related to their life history, ecology, behaviour, physiology and genetics.
A 2007 report from the U.S. Geological Service estimated that as a result of sea-ice decline, today’s population of about 22,000 polar bears would decrease by two-thirds by the year 2050, even with moderate projections for future climate change.
Some species of butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas.
Researcher Bill Fraser has tracked the decline of the Adelie penguins on Antarctica, where their numbers have fallen from 32,000 breeding pairs to 11,000 in 30 years.
Life cycles and behaviour of species that depend on one another may become disrupted. For example, plants could bloom earlier than their pollinating insects become active.

Oceans overwhelmed

Sea surface temperatures have been higher during the past three decades than at any other time since 1880.
Ocean acidification is a direct result of increased human-induced carbon dioxide concentrations in the atmosphere. The ocean absorbs around 25% of total human emissions to the atmosphere each year.
Since the industrial revolution, the acidity of the surface ocean has increased by 30%. This rapid acidification rate jeopardizes the ability of ocean species and ecosystems to adapt.
Ocean acidification affects a range of marine species, including corals, mollusks such as oysters and mussels, and many phytoplankton and zooplankton species that form the base of marine food webs.
The coastal ecosystems of tidal marshes, mangroves and seagrasses sequester and store large quantities of ‘blue carbon’ in both the plants and in the sediment below them.
These Blue Carbon ecosystems are being destroyed at a rapid pace along the world’s coastlines, resulting in significant emissions of carbon dioxide into the atmosphere and ocean and contributing to climate change.

Sources: